So, when you connect on the fly to a database your subject to a
variety of issues, like when the db is not available and when the
db does not have a route.
One of the main reasons why a dev may want to connect on the fly
is because they have too many front ends to hold a persistent
connection on the backends. Since mySQL does not use libevent,
holding open threads to mySQL is much more costly. Threads ==
Memory.
But, that's here nor there. The main purpose of this post is to
talk about how to recover from failed connections that block
apache threads.
Common Failures:
No route to Host
Flapping NIC
Locked Tables
Recovering from a Crash
more of the same.
My Environment:
I have a bunch of webservers (200+) that all have 300 possible
threads (60000 possible connections to a single DB) behind a load
balancer that uses the LB least connections …
Showing entries 1 to 1
Jun
11
2009
Showing entries 1 to 1